A team of scientists from Australia are testing an approach to preventing HIV that takes advantage of the virus' sexual transmission by protecting the human "surfaces" most likely to encounter it first.
The researchers infected mice with a common cold virus that had been altered to include HIV proteins. They then delivered the virus inside the nose to mimic a natural infection to elicit immunity. They also administered an injection of a DNA-based vaccine designed to generate systemic immunity.
“This vaccine approach encompasses two different arms of the immune system: White blood cells that attack the HIV virus, and specific antibodies that recognize and shut down HIV-positive cells,” Branka Grubor-Bauk, senior author of the study and viral immunologist with the Basil Hetzel Institute, said in a statement.
Results of the four-year study, published in Nature’s Scientific Reports, showed that the immune system reacted actively to protect against HIV in mucosal surfaces, which is an important step forward in attempts to defend against the virus at the site of infection.
One reason that previous HIV vaccine trials didn't deliver is that they didn’t trigger an effective immune response in genital mucosal surfaces. The immune system doesn't fight back until the virus has grown and moved further into the body, the scientists said.
So, that's precisely the problem this team of scientists from the University of Adelaide and the Basil Hetzel Institute at Adelaide’s Queen Elizabeth Hospital intend to fix with their vaccine technology.
Calling the study “a glimpse in the right direction,” Grubor-Bauk said the team is hoping to get more funding to take the promising research further. The project is in early stages and the approach needs more verification before it can move into human testing, according to the Australian Broadcasting Corporation,
Elsewhere in HIV vax work, researchers earlier this month launched a large-scale phase 3 trial that involves 5,400 patients in South Africa. The round of trials is designed to test the efficacy and safety of an HIV combo shot comprising two investigational vaccines from Sanofi Pasteur and GlaxoSmithKline. If the study can demonstrate at least 50% effectiveness, it could become the first licensed preventive HIV vaccine.